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into butyric acid and carbon dioxi$.   *|Vl\en the effervesce
begins to  slacken, decant  the  gas^mvn^
tube of lime-water, shake up  and noti^,tIife'Vi@^t)0 fTfe
acid which remains will have a strong smeTT"^^

C2H6CH(CO3H)2 = C3H7CO.OH + C02
See Appendix, p. 256.

Chloral Hydrate, CC13.C

Liebig, Annalen, 1832, 1, 189; Dumas, Aim. Chim. Phys.
1834, 56, 123.

Chloral hydrate is obtained by the action of chlorine upon
ethyl alcohol. The solid chloral alcoholate is formed,
CC13.CHOH.OC.2H5, which, when decomposed with sulphuric
acid, yields chloral, CC13.COH, a liquid which combines with
water to form the crystalline hy'drate.

Properties.It crystallises in prisms, which dissolve easily in
water, alcohol, and liquid hydrocarbons. It has a peculiar
smell ; m. p. 57; b. p. 97*5. It volatilises on evaporating its
aqueous solution.

Reactions.i. Add a few drops of a solution of chloral
hydrate to a little ammonio-silver nitrate solution and warm.
Metallic silver will be deposited.

2.  Add a little caustic soda to a solution of chloral and warm
gently.    The heat of the hand is sufficient for the purpose.    A
smell   of   chloroform   is  at   once   apparent,  CC13.CH(OH)2 +
NaOH==CHCl3 + HCO.ONa-hH.,O.    Sodium formate remains
in solution.

3.  Add a few drops of ammonium sulphide solution and warm
gently.    A brown colouration or precipitate is formed.

PREPARATION 24.
Trichloracetic Acid, CC13,CO.OH.

Dumas, Compt. rend., 1838, 8, 609 ; Clermont, Ann. ChiiiL
PAvs., 1871, (6), 6, 135-

25 grms. chloral hydrate

20     3,    fuming nitric acid ; sp. gr. 1 '5 (see p. id).